This question cannot be standardized because the eye's Dynamicdynamic range is always shifting to adjust to the intensity of light, not only by the ''human apperture''aperture'' but also with the brain's sensitivity atto what the eye is looking at. it'sIt's like a camera with different processors, using the most sensitive to light when it wants and using the highest sensitivity to dark when it wants. I think the dynamic range of the eye is somewhere around 22 to 24 EV.
I have been intreaguedintrigued by this question for a while now, try. Try to take a photo of a milk white exhibition stand with sheets of lightboxes from different angles without having to bracket for exposure and then bracket for white balance sepparatelyseparately and then post processing-processing them later. It is physically impossible.
Just like the eye adjusts to white balance psychologically and that's why the term ''need a fresh eye'' that is because visual perception is also a factor.